centrifugal compressors

Abstract

The centrifugal compressor (CC) provided by the present invention comprises: a shroud component (120) which is installed in a scroll housing (110) at a position radially inward of a compressor scroll flow path (12) and is provided with a shroud portion (121a) radially opposed to the compressor impeller (9); and a first movable component (210) and a second movable component (220) which are arranged in a gap formed between the scroll housing (110) and the shroud component (120).

Description

Technical Field

[0001] The present disclosure relates to a centrifugal compressor. This application claims the benefit of priority based on Japanese Patent Application No. 2020-87639, filed on May 19, 2020, the contents of which are incorporated herein by reference. Background Art

[0002] Patent Document 1 discloses a centrifugal compressor including a compressor housing and a movable member. The compressor housing is divided into a first compressor housing and a second compressor housing. A gap is formed between the first and second compressor housings. The movable member is disposed within the gap. The movable member is configured to be movable within the gap.

[0003] [Prior art literature]

[0004] [Patent Document]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-255381 Summary of the Invention

[0006] [Problems to be Solved by the Invention]

[0007] In Patent Document 1, the dividing surface between the first compressor housing and the second compressor housing is exposed to the outside. The dividing surface is a major factor causing foreign matter to enter the compressor housing from the outside.

[0008] The present disclosure provides a centrifugal compressor capable of suppressing the intrusion of foreign matter into the interior of a compressor housing.

[0009] [Means for solving the problem]

[0010] In order to solve the above-mentioned problems, a centrifugal compressor involved in a technical solution of the present disclosure includes: a scroll casing, which forms a scroll flow path; a shroud component, which is installed in the scroll casing at a position radially inward of the scroll flow path and forms a shroud portion radially opposite to the compressor impeller; and a throttling component, which is arranged in a gap formed between the scroll casing and the shroud component.

[0011] The throttle member may be arranged at a position farther from the shroud portion than the front edge of the compressor impeller.

[0012] A sealing member disposed between the scroll casing and the shroud member may be provided.

[0013] The shroud member may form a portion of the inner peripheral surface of the scroll flow path.

[0014] The scroll casing may include an abutment portion that abuts against the shroud member in the axial direction of the compressor impeller and is arranged radially outside the throttle member.

[0015] Alternatively, the shroud member may comprise a wear-resistant material.

[0016] The cover member may have a hollow portion.

[0017] [Effects of the Invention]

[0018] According to the present disclosure, it is possible to suppress the intrusion of foreign matter into the interior of the compressor housing. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic cross-sectional view of a supercharger.

[0020] Figure 2 yes Figure 1 Extraction diagram of the dotted part.

[0021] Figure 3 yes Figure 2 Cross-sectional view along line III-III.

[0022] Figure 4 This is the first diagram for explaining the operation of the link mechanism.

[0023] Figure 5 This is a second diagram for explaining the operation of the link mechanism.

[0024] Figure 6 This is the third diagram for explaining the operation of the link mechanism.

[0025] Figure 7 It is a schematic cross-sectional view showing the structure of a compressor housing in a comparative example.

[0026] Figure 8 It is a schematic side view of a compressor housing of a comparative example.

[0027] Figure 9 The compressor housing of the comparative example Figure 8 Sectional view along line IX-IX.

[0028] Figure 10 The compressor housing of this embodiment Figure 2 Sectional view along the XX line.

[0029] Figure 11 It is a schematic cross-sectional view showing the structure of a compressor housing in a first modified example.

[0030] Figure 12 It is a schematic cross-sectional view showing the structure of a compressor housing in a second modified example. DETAILED DESCRIPTION

[0031] Hereinafter, an embodiment of the present disclosure will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values ​​shown in the embodiments are merely illustrative for ease of understanding and, unless otherwise stated, do not limit the present disclosure. Note that in this specification and the accompanying drawings, elements having substantially the same function and structure are denoted by the same reference numerals, thereby omitting any repeated description of these elements. In addition, elements not directly related to the present disclosure are omitted from illustration.

[0032] Figure 1 Schematic cross-sectional view of the supercharger TC. Figure 1 The direction of arrow L shown is explained as the left side of the supercharger TC. Figure 1 The direction of arrow R shown is explained as the right side of the supercharger TC. Figure 1 As shown, supercharger TC includes a supercharger body 1. The supercharger body 1 includes a bearing housing 2, a turbine housing 3, a compressor housing 100, and a connecting rod mechanism 200. Details of the connecting rod mechanism 200 will be described later. The turbine housing 3 is connected to the left side of the bearing housing 2 via fastening bolts 4. The compressor housing 100 is connected to the right side of the bearing housing 2 via fastening bolts 5.

[0033] The bearing housing 2 has a receiving hole 2a formed therein. The receiving hole 2a extends through the turbocharger TC in the left-right direction. The bearing 6 is disposed in the receiving hole 2a. Figure 1 In the figure, a fully floating bearing is shown as an example of bearing 6. However, bearing 6 may also be another radial bearing, such as a semi-floating bearing or a rolling bearing. A portion of shaft 7 is disposed in receiving hole 2a. Shaft 7 is rotatably supported by bearing 6. A turbine impeller 8 is provided at the left end of shaft 7. Turbine impeller 8 is rotatably housed within turbine housing 3. A compressor impeller 9 is provided at the right end of shaft 7. Compressor impeller 9 is rotatably housed within compressor housing 100.

[0034] An air intake port 10 is formed in the compressor housing 100. The air intake port 10 opens on the right side of the supercharger TC. The air intake port 10 is connected to an air filter (not shown). A diffuser flow path 11 is formed between the bearing housing 2 and the compressor housing 100. The diffuser flow path 11 increases the pressure of the air. The diffuser flow path 11 is formed in an annular shape from the inner side to the outer side of the radial direction (hereinafter referred to as the radial direction) of the shaft 7 (compressor impeller 9). The diffuser flow path 11 is connected to the air intake port 10 via the compressor impeller 9 on the inner side of the radial direction.

[0035] A compressor scroll flow path 12 is formed in the compressor housing 100. The compressor scroll flow path 12 is formed in an annular shape. The compressor scroll flow path 12 is located radially outward of the compressor impeller 9. The compressor scroll flow path 12 is connected to the intake port of the engine (not shown) and the diffuser flow path 11. When the compressor impeller 9 rotates, air is sucked into the compressor housing 100 from the intake port 10. The sucked air is pressurized and accelerated during the process of flowing between the blades of the compressor impeller 9. The pressurized and accelerated air is boosted in the diffuser flow path 11 and the compressor scroll flow path 12. The boosted air flows out from the exhaust port (not shown) and is guided to the intake port of the engine.

[0036] The compressor housing 100 side in the supercharger TC functions as a centrifugal compressor (compressor) CC. In the following, the centrifugal compressor CC is described as a component driven by the turbine impeller 8. However, this is not limited to this, and the centrifugal compressor CC can also be driven by an engine (not shown) or an electric motor (motor) (not shown). In this way, the centrifugal compressor CC can be assembled into a device other than the supercharger TC, or it can be a single unit. The centrifugal compressor CC includes a compressor housing 100, a compressor impeller 9, and a connecting rod mechanism 200 described later.

[0037] An exhaust port 13 is formed in the turbine housing 3. Exhaust port 13 opens on the left side of the supercharger TC. Exhaust port 13 is connected to an exhaust gas purification device (not shown). A communication flow path 14 and a turbine scroll flow path 15 are formed in the turbine housing 3. The turbine scroll flow path 15 is located radially outward of the turbine impeller 8. The communication flow path 14 is located between the turbine impeller 8 and the turbine scroll flow path 15.

[0038] The turbine scroll flow path 15 is connected to a gas inlet (not shown). Exhaust gas discharged from the exhaust manifold of the engine (not shown) is guided to the gas inlet. The communication flow path 14 connects the turbine scroll flow path 15 to the exhaust port 13 via the turbine impeller 8. Exhaust gas introduced from the gas inlet into the turbine scroll flow path 15 passes between the communication flow path 14 and the blades of the turbine impeller 8 and is guided to the exhaust port 13. The exhaust gas rotates the turbine impeller 8 during its flow.

[0039] The rotational force of the turbine impeller 8 is transmitted to the compressor impeller 9 via the shaft 7. As described above, the air is pressurized by the rotational force of the compressor impeller 9 and is guided to the intake port of the engine.

[0040] Figure 2 yes Figure 1 The extracted image of the dotted part of Figure 2 As shown, the compressor housing 100 is divided into a scroll housing 110 and a shroud member 120. The scroll housing 110 and the shroud member 120 are constructed as separate bodies.

[0041] A through-hole 111 is formed in the scroll housing 110. Through-hole 111 extends through the scroll housing 110 in the axial direction of the shaft 7 (hereinafter referred to as the axial direction). An intake port 10 is provided at the end of the through-hole 111 facing away from the bearing housing 2. The scroll housing 110 also has a connection surface for connection to the bearing housing 2, and a compressor scroll flow path 12 is formed near the connection surface.

[0042] Through-hole 111 includes a parallel portion 111a, a reduced diameter portion 111b, and a recessed portion 111c. Parallel portion 111a is located at the position farthest from bearing housing 2 in through-hole 111. The inner diameter of parallel portion 111a is substantially constant across the axial direction. Reduced diameter portion 111b is located closer to bearing housing 2 than parallel portion 111a. Reduced diameter portion 111b is continuous with parallel portion 111a. The inner diameter of reduced diameter portion 111b decreases as it approaches bearing housing 2.

[0043] The recessed portion 111c is positioned closer to the bearing housing 2 than the reduced diameter portion 111b. The recessed portion 111c is recessed radially outward relative to the reduced diameter portion 111b and the parallel portion 111a. That is, the inner diameter of the recessed portion 111c is larger than the inner diameters of the reduced diameter portion 111b and the parallel portion 111a. A shroud member 120 is positioned in the recessed portion 111c. The shroud member 120 abuts against the recessed portion 111c. The shroud member 120 is mounted in the scroll casing 110 radially inward of the compressor scroll flow path 12.

[0044] In this embodiment, the shield member 120 is pressed into the recessed portion 111c. However, this is not limiting, and the shield member 120 may be bonded to the scroll housing 110. Alternatively, the shield member 120 may be attached to the scroll housing 110 via a fitting ring (snapping ring). Furthermore, the shield member 120 may include a flange portion (not shown) that is screwed to the scroll housing 110. The shield member 120 is housed within the recessed portion 111c (the scroll housing 110).

[0045] A through hole 121 is formed in the shield member 120. The through hole 121 penetrates the shield member 120 in the axial direction. The minimum inner diameter of the through hole 121 is approximately equal to the minimum inner diameter of the through hole 111 (the reduced diameter portion 111b). A shield portion 121a is formed on the inner wall of the through hole 121. The shield portion 121a is opposed to the compressor impeller 9 from the radial outside. The outer diameter of the compressor impeller 9 becomes larger as it moves away from the leading edge end (front edge) LE of the blades of the compressor impeller 9. The shield portion 121a has a shape that is similar to the outer shape of the compressor impeller 9. The inner diameter of the shield portion 121a is slightly larger than the outer diameter of the compressor impeller 9. Therefore, the inner diameter of the shield portion 121a becomes larger from the front edge LE toward the bearing housing 2 side.

[0046] The shroud member 120 is made of a wear-resistant material. In this embodiment, at least the shroud portion 121a of the shroud member 120 is made of a wear-resistant material. As a result, when the rotating compressor impeller 9 contacts the shroud portion 121a, the shroud member 120 is cut by the compressor impeller 9. As a result, the gap between the shroud portion 121a and the compressor impeller 9 can be reduced. However, the shroud member 120 does not need to be made of a wear-resistant material.

[0047] The through hole 111 of the scroll housing 110 and the through hole 121 of the shroud member 120 form an intake air passage 130. That is, the intake air passage 130 is formed in the compressor housing 100. The intake air passage 130 is connected to the diffuser passage 11 (see FIG. 1 ) via the air cleaner (not shown) via the intake port 10. Figure 1 The air cleaner side of the intake air flow path 130 (the intake port 10 side) is regarded as the upstream side of the intake air, and the diffuser flow path 11 side of the intake air flow path 130 is regarded as the downstream side of the intake air.

[0048] The compressor impeller 9 is disposed in the intake air flow path 130. The cross-sectional shape of the intake air flow path 130 (through holes 111, 121) perpendicular to the axial direction is, for example, a circle centered on the rotation axis of the compressor impeller 9. However, the cross-sectional shape of the intake air flow path 130 is not limited to this and may also be, for example, an elliptical shape.

[0049] One end of the dividing surface Ds1 between the scroll casing 110 and the shroud member 120 is located on the inner surface of the diffuser flow path 11, and the other end is located on the inner surface of the intake flow path 130 upstream of the leading edge LE. In this embodiment, the dividing surface Ds1 spans between the diffuser flow path 11 and the intake flow path 130. The dividing surface Ds1 is located within the compressor casing 100 from one end to the other. The dividing surface Ds1 is not exposed on the outer surface of the compressor casing 100.

[0050] A sealing member 140 is disposed between the recessed portion 111c of the scroll casing 110 and the shroud member 120. The sealing member 140 is disposed midway along the dividing plane Ds1. The sealing member 140 suppresses the flow rate of air flowing through the gap between the scroll casing 110 and the shroud member 120. However, the sealing member 140 is not essential and may not be disposed between the recessed portion 111c and the shroud member 120.

[0051] An opposing surface 120a is formed on the inner diameter side of the side surface (axial end surface) of the shroud member 120. An opposing surface 110a is formed in the scroll housing 110, which is axially opposed to the opposing surface 120a. The opposing surface 110a is located closer to the compressor impeller 9 than the reduced diameter portion 111b, and is located further away from the compressor impeller 9 than the recessed portion 111c. The opposing surface 120a of the shroud member 120 is axially separated from the opposing surface 110a of the shroud member 110. That is, a gap S is formed between the shroud member 110 and the shroud member 120. The gap S is arranged on the upstream side of the intake air relative to the compressor impeller 9 in the axial direction of the compressor impeller 9. That is, the gap S is arranged closer to the intake port 10 than the leading edge LE. The gap S is arranged closer to the bearing housing 2 than the reduced diameter portion 111b. A throttle member (a first movable member 210 and a second movable member 220 ) described in detail later is disposed in the gap S. Specifically, the first movable member 210 and the second movable member 220 are disposed at positions farther from the shroud portion 121 a than the front edge LE of the compressor impeller 9 .

[0052] An abutment surface 120b is formed on the outer diameter side of the side surface (axial end surface) of the shroud member 120. An abutment surface 110b is formed on the scroll housing 110, which is axially opposed to the abutment surface 120b. The abutment surface 120b of the shroud member 120 abuts the abutment surface 110b of the shroud housing 110 in the axial direction. The abutment surface 110b of the shroud housing 110 is located closer to the compressor impeller 9 than the opposing surface 110a. That is, the shroud housing 110 has a protrusion (abutment portion) 111d that protrudes from the opposing surface 110a toward the compressor impeller 9. In this embodiment, the shroud housing 110 has an abutment portion 111d including the abutment surface 110b that abuts the shroud member 120 in the axial direction. The abutment portion 111d is arranged radially outward of the first movable member 210 and the second movable member 220. The contact portion 111d contacts the shroud member 120, thereby determining the axial position of the shroud member 120. Furthermore, by providing the contact portion 111d on the scroll casing 110, the press-fit margin of the shroud member 120 can be reduced. However, the present invention is not limited thereto, and the contact portion 111d may also be provided on the shroud member 120.

[0053] Figure 3 yes Figure 2 The III-III line cross-sectional view. Figure 3 As shown, the gap S includes a receiving groove 112, a bearing hole 113, and a receiving hole 114. In this embodiment, the receiving groove 112, the bearing hole 113, and the receiving hole 114 are formed in the scroll housing 110. However, the present invention is not limited to this, and the receiving groove 112, the bearing hole 113, and the receiving hole 114 may also be formed in the shield member 120.

[0054] The receiving groove 112 is formed in a roughly annular shape. The receiving groove 112 is connected to the through hole 111 on the radial inner side. The bearing hole 113 is formed on the wall surface of the receiving groove 112 on the side of the air intake port 10. The bearing hole 113 extends axially from the receiving groove 112 toward the air intake port 10. A plurality of bearing holes 113 are separately provided in the rotation direction of the shaft 7 (hereinafter referred to as the rotation direction, the circumferential direction). In the present embodiment, two bearing holes 113 are provided. The two bearing holes 113 are arranged at positions offset by 180° in the rotation direction.

[0055] The receiving hole 114 is formed on the wall surface of the receiving groove 112 on the air inlet 10 side. The receiving hole 114 is recessed in the axial direction from the receiving groove 112 toward the air inlet 10 side. The receiving hole 114 is substantially arc-shaped and is circumferentially separated from the two bearing holes 113.

[0056] The link mechanism 200 includes a first movable member 210, a second movable member 220, a connecting member 230, and a rod 240. The link mechanism 200 is arranged upstream of the compressor impeller 9 in the intake flow path 130 in the axial direction.

[0057] The first movable member 210 is disposed in the housing groove 112. The first movable member 210 includes a curved portion 211 and an arm portion 212. The curved portion 211 extends circumferentially of the compressor impeller 9. The curved portion 211 is generally semicircular in shape. The first end surface 211a and the second end surface 211b of the curved portion 211 extend parallel to the radial and axial directions. However, the first end surface 211a and the second end surface 211b may be inclined relative to the radial and axial directions.

[0058] An arm portion 212 is provided on the first end surface 211a side of the curved portion 211. The arm portion 212 continues radially outward from the first end surface 211a side of the curved portion 211. The arm portion 212 also extends from the first end surface 211a toward the second movable member 220 side.

[0059] The second movable member 220 is disposed in the housing groove 112. The second movable member 220 includes a curved portion 221 and an arm portion 222. The curved portion 221 extends circumferentially along the compressor impeller 9. The curved portion 221 is generally semicircular in shape. The first end surface 221a and the second end surface 221b of the curved portion 221 extend parallel to each other in the radial and axial directions. However, the first end surface 221a and the second end surface 221b may be inclined relative to the radial and axial directions.

[0060] An arm portion 222 is provided on the first end surface 221a side of the curved portion 221. The arm portion 222 continues radially outward from the first end surface 221a side of the curved portion 221. The arm portion 222 also extends from the first end surface 221a toward the first movable member 210 side.

[0061] The curved portion 211 faces the rotational axis of the compressor impeller 9 across the curved portion 221. The first end surface 211a of the curved portion 211 and the second end surface 221b of the curved portion 221 are circumferentially opposed. The second end surface 211b of the curved portion 211 and the first end surface 221a of the curved portion 221 are circumferentially opposed. As described in detail later, the first movable member 210 and the second movable member 220 are configured so that the curved portions 211 and 221 are movable in the radial direction.

[0062] The connecting member 230 connects the first movable member 210 and the second movable member 220 to the rod 240. The connecting member 230 is disposed in the storage hole 114. That is, the connecting member 230 is disposed closer to the air inlet 10 than the first movable member 210 and the second movable member 220. The connecting member 230 has a generally arcuate shape. The radial width of the connecting member 230 is smaller than the radial width of the storage hole 114. The circumferential length of the connecting member 230 is shorter than the circumferential length of the storage hole 114.

[0063] The connecting member 230 is formed with a first bearing hole 231 on one end side in the circumferential direction, and a second bearing hole 232 on the other end side. The first bearing hole 231 is opened on the surface of the connecting member 230 that is opposite to the first movable member 210 in the axial direction. The second bearing hole 232 is opened on the surface of the connecting member 230 that is opposite to the second movable member 220 in the axial direction. The first bearing hole 231 and the second bearing hole 232 extend in the axial direction. Here, the first bearing hole 231 and the second bearing hole 232 are composed of non-through holes. However, the first bearing hole 231 and the second bearing hole 232 may also pass through the connecting member 230 in the axial direction.

[0064] The connecting member 230 includes a rod connecting portion 233. The rod connecting portion 233 protrudes axially from a surface of the connecting member 230 that is away from the first movable member 210 and the second movable member 220. The rod connecting portion 233 is substantially cylindrical in shape and is located approximately in the center of the connecting member 230 in the circumferential direction.

[0065] Rod 240 is generally cylindrical in shape. A bearing hole 241 is formed at one end of rod 240, and the other end is connected to an actuator (described later). Bearing hole 241 extends axially. Bearing hole 241 is slightly larger than rod connection portion 233.

[0066] An insertion hole (not shown) is formed in the scroll casing 110. One end of the rod 240 is inserted into the insertion hole. The insertion hole restricts movement of the rod 240 in a direction perpendicular to the central axis. Furthermore, the insertion hole guides movement of the rod 240 in the direction of the central axis.

[0067] The bearing hole 241 of the rod 240 is located within the insertion hole. A connecting hole 116 is formed on the inner wall of the insertion hole, communicating with the receiving hole 114. Connecting hole 116 is formed approximately in the middle of the circumference of receiving hole 114. The width of connecting hole 116 in the direction of the rod 240's central axis is greater than the width of the rod 240 in a direction perpendicular to the central axis. In other words, connecting hole 116 is an elongated hole. The width of connecting hole 116 in the short-side direction is slightly greater than the outer diameter of the rod connecting portion 233.

[0068] Rod connecting portion 233 is inserted into bearing hole 241 via communicating hole 116. Thus, rod 240 is connected to connecting member 230. The circumferential length of housing hole 114 is longer than that of connecting member 230. The radial width of housing hole 114 is greater than that of connecting member 230. Therefore, connecting member 230 is allowed to move within housing hole 114 within a plane perpendicular to the rotational axis of compressor impeller 9.

[0069] The first movable member 210 and the second movable member 220 are housed in the housing groove 112. Specifically, the first movable member 210 and the second movable member 220 are housed in the gap S formed between the scroll casing 110 and the shroud member 120. The inner diameter of the housing groove 112 is larger than the outer diameter of the curved portion 211 of the first movable member 210. The inner diameter of the housing groove 112 is also larger than the outer diameter of the curved portion 221 of the second movable member 220. Therefore, the first movable member 210 and the second movable member 220 are allowed to move within the housing groove 112 within a plane perpendicular to the rotational axis of the compressor impeller 9.

[0070] The first movable member 210 includes a connecting shaft 213 and a rotating shaft 214. The connecting shaft 213 and the rotating shaft 214 protrude axially from the surface of the first movable member 210 facing the air inlet 10. The connecting shaft 213 and the rotating shaft 214 extend substantially parallel to each other. The connecting shaft 213 and the rotating shaft 214 are substantially cylindrical in shape.

[0071] The outer diameter of connecting shaft portion 213 is smaller than the inner diameter of first bearing hole 231 of connecting member 230. Connecting shaft portion 213 is inserted through first bearing hole 231. Connecting shaft portion 213 is rotatably supported in first bearing hole 231. The outer diameter of rotating shaft portion 214 is smaller than the inner diameter of bearing hole 113 of scroll casing 110. Rotating shaft portion 214 is inserted through the vertically upper bearing hole 113 of the two bearing holes 113. Rotating shaft portion 214 is rotatably supported in bearing hole 113.

[0072] The second movable member 220 includes a connecting shaft 223 and a rotating shaft 224. The connecting shaft 223 and the rotating shaft 224 protrude axially from the surface of the second movable member 220 facing the air inlet 10. The connecting shaft 223 and the rotating shaft 224 extend substantially parallel to each other. The connecting shaft 223 and the rotating shaft 224 are substantially cylindrical.

[0073] The outer diameter of connecting shaft portion 223 is smaller than the inner diameter of second bearing hole 232 of connecting member 230. Connecting shaft portion 223 is inserted through second bearing hole 232. Connecting shaft portion 223 is rotatably supported in second bearing hole 232. The outer diameter of rotating shaft portion 224 is smaller than the inner diameter of bearing hole 113 of scroll casing 110. Rotating shaft portion 224 is inserted through the vertically lower bearing hole 113 of the two bearing holes 113. Rotating shaft portion 224 is rotatably supported in bearing hole 113.

[0074] Thus, the link mechanism 200 is composed of a four-link mechanism. The four links (links) are the first movable member 210, the second movable member 220, the scroll casing 110, and the connecting member 230. The four-link mechanism 200 forms a limited linkage, making it easier to control one degree of freedom.

[0075] Figure 4 This is the first diagram for explaining the operation of the link mechanism 200. Figure 4 、 Figure 5 、 Figure 6 1 shows a diagram of the link mechanism 200 viewed from the air inlet 10 side. Figure 4 As shown, the drive shaft of the actuator 250 is connected to the rod 240 .

[0076] exist Figure 4 In the configuration shown, the first movable member 210 and the second movable member 220 are in contact with each other. Figure 2 and Figure 3 As shown, the radially inner portion of the first movable member 210, namely the protrusion 215, protrudes (is exposed) into the intake air passage 130. The radially inner portion of the second movable member 220, namely the protrusion 225, protrudes (is exposed) into the intake air passage 130. The positions of the first movable member 210 and the second movable member 220 in this state are referred to as the protruding position (or throttle position).

[0077] like Figure 4As shown, in the protruding position, the circumferential ends 215a and 215b of the protrusion 215 abut against the circumferential ends 225a and 225b of the protrusion 225. The protrusions 215 and 225 form an annular hole 260. The inner diameter of the annular hole 260 is smaller than the inner diameter of the portion of the intake air passage 130 where the protrusions 215 and 225 protrude. The inner diameter of the annular hole 260 is, for example, smaller than the inner diameter of any portion of the intake air passage 130.

[0078] Figure 5 This is a second diagram for explaining the operation of the link mechanism 200 . Figure 6 3 is a diagram for explaining the operation of the link mechanism 200. The actuator 250 moves the link 240 in a direction intersecting the axial direction of the compressor impeller 9 ( Figure 5 、 Figure 6 Direct movement in the up and down directions. Figure 5 and Figure 6 In the middle, rod 240 from Figure 4 The position shown is moved upward. Figure 5 Compared with the configuration of Figure 6 The configuration relative to Figure 4 The movement amount of the rod 240 of the configuration is large.

[0079] When the rod 240 moves, the connecting member 230 moves to the Figure 5 、 Figure 6 At this time, connecting member 230 is allowed to rotate about rod connecting portion 233. Furthermore, there is a slight amount of play in the inner diameter of bearing hole 241 of rod 240 relative to the outer diameter of rod connecting portion 233. Therefore, connecting member 230 is allowed to slightly move in a plane perpendicular to the axial direction of compressor impeller 9.

[0080] As described above, the link mechanism 200 is a four-link link mechanism. The connecting member 230, the first movable member 210, and the second movable member 220 exhibit one degree of freedom relative to the scroll casing 110. Specifically, the connecting member 230 is within the above-mentioned allowable range. Figure 5 、 Figure 6 While rotating slightly counterclockwise, it also swings slightly left and right.

[0081] The rotating shaft portion 214 in the first movable member 210 is supported by the scroll housing 110. The movement of the rotating shaft portion 214 in the plane direction perpendicular to the axial direction of the compressor impeller 9 is restricted. The connecting shaft portion 213 is supported by the connecting member 230. Since the movement of the connecting member 230 is allowed, the connecting shaft portion 213 is provided to be able to move in the plane direction perpendicular to the axial direction of the compressor impeller 9. As a result, as the connecting member 230 moves, the first movable member 210 rotates along the rotating shaft portion 214 as the center of rotation. Figure 5 、 Figure 6 Clockwise rotation in.

[0082] Similarly, the rotating shaft portion 224 in the second movable member 220 is axially supported by the scroll housing 110. The movement of the rotating shaft portion 224 in the plane direction perpendicular to the axial direction of the compressor impeller 9 is restricted. The connecting shaft portion 223 is axially supported by the connecting member 230. Since the movement of the connecting member 230 is allowed, the connecting shaft portion 223 is configured to be able to move in the plane direction perpendicular to the axial direction of the compressor impeller 9. As a result, as the connecting member 230 moves, the second movable member 220 rotates along the rotating shaft portion 224 as the center of rotation. Figure 5 、 Figure 6 Clockwise rotation in.

[0083] In this way, the first movable member 210 and the second movable member 220 are arranged in accordance with Figure 5 、 Figure 6 The protrusions 215 and 225 move radially outward from the protruding position (retracted position). In the retracted position, for example, the protrusions 215 and 225 are in the same plane as the inner wall surface of the air intake passage 130, or are located radially outward from the inner wall surface of the air intake passage 130. When moving from the retracted position to the protruding position, the first movable member 210 and the second movable member 220 are arranged in a manner such that the first movable member 210 and the second movable member 220 move radially outward from the protruding position. Figure 6 、 Figure 5 、 Figure 4 In this way, the first movable member 210 and the second movable member 220 switch between the protruding position and the retracted position according to the rotation angle with the rotation shaft portions 214 and 224 as the rotation center.

[0084] In this way, the first movable member 210 and the second movable member 220 are configured to be movable to a protruding position protruding into the intake air flow path 130 and a retracted position retracting from the intake air flow path 130. In the present embodiment, the first movable member 210 and the second movable member 220 move in the radial direction of the compressor impeller 9. However, this is not limiting, and the first movable member 210 and the second movable member 220 may also rotate around the rotation axis (circumferential direction) of the compressor impeller 9 and move to the protruding position and the retracted position. For example, the first movable member 210 and the second movable member 220 may also be shutter blades having two or more blades.

[0085] When located at the retracted position (hereinafter also referred to as the retracted position state), the first movable member 210 and the second movable member 220 do not protrude into the intake air flow path 130. Therefore, the pressure loss of intake air (air) flowing in the intake air flow path 130 is reduced.

[0086] In addition, if Figure 2As shown, when the first movable member 210 and the second movable member 220 are in the protruding position (hereinafter also referred to as the protruding position state), the protrusions 215 and 225 protrude into the intake air flow path 130. In other words, the protrusions 215 and 225 are disposed within the intake air flow path 130. When the protrusions 215 and 225 protrude into the intake air flow path 130, the flow path cross-sectional area of ​​the intake air flow path 130 decreases.

[0087] Here, as the flow rate of air flowing into the compressor impeller 9 decreases, the air compressed by the compressor impeller 9 may flow back in the intake air flow path 130 (i.e., the air flows from the downstream side to the upstream side). In other words, as the flow rate of air flowing into the compressor impeller 9 decreases, a reverse flow phenomenon called surge may occur.

[0088] exist Figure 2 In the projected position shown, the projections 215 and 225 are located radially inward of the outermost diameter end of the leading edge LE of the compressor impeller 9. Consequently, air flowing back through the intake air passage 130 is blocked by the projections 215 and 225. Therefore, the first movable member 210 and the second movable member 220 in the projected position can suppress the backflow of air within the intake air passage 130.

[0089] Furthermore, as the cross-sectional area of ​​the intake airflow path 130 decreases, the flow velocity of the air flowing into the compressor impeller 9 increases. This reduces the angle of incidence of the compressor impeller 9 relative to the blades, stabilizing the flow of air. Consequently, the occurrence of surge in the centrifugal compressor CC can be suppressed. Specifically, by having the protrusions 215 and 225 protrude into the intake airflow path 130, the centrifugal compressor CC of this embodiment can expand its operating range toward lower flow rates.

[0090] Thus, the first movable member 210 and the second movable member 220 constitute a throttling member that throttles the intake air flow path 130. That is, in this embodiment, the link mechanism 200 constitutes a throttling mechanism that throttles the intake air flow path 130. By driving the link mechanism 200, the first movable member 210 and the second movable member 220 can change the flow path cross-sectional area of ​​the intake air flow path 130.

[0091] Figure 7 2 is a schematic cross-sectional view showing the structure of a compressor housing 300 in a comparative example. Components substantially equivalent to those of the centrifugal compressor CC of the above-described embodiment are denoted by the same reference numerals and their descriptions are omitted.

[0092] like Figure 7As shown, the compressor housing 300 of the comparative example is divided into a first compressor housing 310 and a second compressor housing 320. A gap S is formed between the first compressor housing 310 and the second compressor housing 320. In the gap S, the first movable member 210 and the second movable member 220 are arranged.

[0093] In the compressor housing 300 of the comparative example, a dividing surface Ds2 between the first compressor housing 310 and the second compressor housing 320 is exposed to the outside. The dividing surface Ds2 connects the outside and the inside of the compressor housing 300. The dividing surface Ds2 is a major factor in the intrusion of foreign matter from the outside into the compressor housing 300.

[0094] Figure 8 FIG is a schematic side view of a compressor housing 300 of a comparative example. Figure 8 As shown, when assembling the compressor housing 300 of the comparative example, the first compressor housing 310 is positioned vertically below, and the second compressor housing 320 is positioned vertically above. Furthermore, the second compressor housing 320 is brought closer to the first compressor housing 310 from the vertical above toward the vertical below, thereby connecting the first compressor housing 310 and the second compressor housing 320. In this manner, the compressor housing 300 of the comparative example is assembled.

[0095] Figure 9 The compressor housing 300 of the comparative example Figure 8 The IX-IX line cross-sectional view. Figure 9 As shown, the maximum outer diameter of the first compressor housing 310 is smaller than the maximum outer diameter of the second compressor housing 320. Therefore, when assembling the second compressor housing 320 from the vertical upper side of the first compressor housing 310, it is difficult to visually inspect the first compressor housing 310. As a result, assembly of the compressor housing 300 becomes difficult.

[0096] Figure 10 The compressor housing 100 of this embodiment Figure 2 Sectional view along the XX line. Figure 10 As shown in FIG. 1 , the compressor housing 100 of this embodiment includes a scroll housing 110 and a shroud member 120. The dividing surface Ds1 between the scroll housing 110 and the shroud member 120 is located inside the compressor housing 100. That is, the dividing surface Ds1 is not exposed to the outside of the compressor housing 100. Therefore, according to the compressor housing 100 of this embodiment, Figure 7 Compared with the compressor housing 300 of the comparative example in which the dividing surface Ds2 shown is exposed to the outside, the intrusion of foreign matter can be reduced.

[0097] When assembling the compressor housing 100 of this embodiment, the scroll housing 110 is positioned vertically below, and the shroud member 120 is positioned vertically above. The shroud member 120 is then moved closer to the scroll housing 110 from the vertical above toward the vertical below, thereby connecting the scroll housing 110 and the shroud member 120. In this manner, the compressor housing 100 of this embodiment is assembled.

[0098] like Figure 10 As shown, the maximum outer diameter of the shroud member 120 is smaller than the maximum outer diameter of the scroll casing 110. Therefore, when assembling the shroud member 120 from the vertically upper side of the scroll casing 110, the shroud member 120 can be assembled while being visually observed. As a result, assembly of the compressor casing 100 is facilitated.

[0099] Figure 11 This is a schematic cross-sectional view showing the structure of a compressor housing 400 in a first modified example. Components substantially identical to those of the centrifugal compressor CC in the aforementioned embodiment are denoted by the same reference numerals, and their descriptions are omitted. The structure of the shroud member 420 of the compressor housing 400 in the first modified example differs from that in the aforementioned embodiment. The remaining structure is identical to that of the compressor housing 100 in the aforementioned embodiment.

[0100] The shroud component 420 of the first modified example includes a shroud portion 121a and a protrusion 421. The shroud portion 121a has a substantially constant outer diameter that is smaller than the minimum inner diameter of the compressor scroll flow path 12. The protrusion 421 is substantially annular in shape. The protrusion 421 is disposed on the downstream side of the shroud portion 121a. The protrusion 421 protrudes radially outward from the shroud portion 121a. The protrusion 421 forms a portion of the inner circumferential surface of the compressor scroll flow path 12. The maximum outer diameter of the protrusion 421 is smaller than the maximum outer diameter of the scroll casing 110. The dividing surface Ds1 is connected to the upstream side of the protrusion 421. One end of the dividing surface Ds1 is located on the inner surface of the compressor scroll flow path 12, and the other end is located on the inner surface of the intake flow path 130 upstream of the leading edge LE. In the first modified example, the dividing surface Ds1 spans between the compressor scroll flow path 12 and the intake flow path 130. The dividing surface Ds1 is located from one end to the other end inside the compressor housing 400. The dividing surface Ds1 is not exposed on the outer surface of the compressor housing 400.

[0101] According to the first modification, the same functions and effects as those of the above-described embodiment can be achieved. Furthermore, the shroud member 420 of the first modification forms a portion of the inner circumferential surface of the compressor scroll flow path 12. This facilitates the manufacture (casting) of the shroud member 120 having the compressor scroll flow path 12.

[0102] Figure 12This is a schematic cross-sectional view showing the structure of a compressor housing 500 in a second modified example. Components substantially identical to those of the centrifugal compressor CC in the aforementioned embodiment are denoted by the same reference numerals, and their descriptions are omitted. The structure of the shroud member 520 of the compressor housing 500 in the second modified example differs from that in the aforementioned embodiment. The remaining structure is identical to that of the compressor housing 100 in the aforementioned embodiment.

[0103] The shield member 520 of the second modified example has a hollow portion 521. The hollow portion 521 does not open on the inner peripheral surface of the shield member 520. The hollow portion 521 opens on the outer peripheral surface of the shield member 520. However, the hollow portion 521 may not open on the outer peripheral surface of the shield member 520. For example, the hollow portion 521 may not open on the outside of the shield member 520, but may form a closed space inside. That is, the hollow portion 521 forms a closed space inside the shield member 520. The hollow portion 521 is difficult to communicate with the intake air flowing outside the shield member 520.

[0104] The second variation achieves the same functions and effects as the aforementioned embodiment. Furthermore, the shroud member 520 of the second variation includes a hollow portion 521. Consequently, the compressor housing 500 of the second variation can be made lighter than the compressor housings 100 and 400 of the aforementioned embodiment and the first variation. Furthermore, an air layer is formed in the hollow portion 521. Therefore, when the shroud member 520 is formed with the hollow portion 521, thermal insulation can be improved compared to when the hollow portion 521 is not formed.

[0105] While one embodiment of the present disclosure has been described above with reference to the accompanying drawings, it goes without saying that the present disclosure is not limited to this embodiment. It is clear that those skilled in the art will be able to devise various variations or modifications within the scope of the claims, and these variations or modifications will naturally fall within the technical scope of the present disclosure.

[0106] In the above-described embodiment, first modification, and second modification, examples are described in which the gap S is formed upstream of the compressor impeller 9 in terms of the intake air. However, this is not limiting; the gap S may also be formed downstream of the compressor impeller 9 in terms of the intake air. For example, the gap S may be formed between the compressor impeller 9 and the compressor scroll flow path 12. In other words, the gap S may also communicate with the diffuser flow path 11. In this manner, the gap S only needs to be formed between the scroll casing 110 and the shroud member 120, 420, or 520.

[0107] In the above-described embodiment, first modification, and second modification, examples are described in which the sealing member 140 is provided between the recessed portion 111c and the shroud member 120. However, the sealing member 140 is not a required structure. For example, if the shroud members 120, 420, or 520 are press-fitted into the scroll casing 110, the sealing member 140 may not be provided.

[0108] [Explanation of symbols]

[0109] 9: Compressor impeller 12: Compressor scroll flow path (scroll flow path) 100: Compressor housing 110: Scroll housing 111d: Abutment portion 120: Guard component 121a: Guard portion 140: Sealing component 210: First movable component (throttling component) 220: Second movable component (throttling component) 400: Compressor housing 420: Guard component 421: Protrusion 500: Compressor housing 520: Guard component 521: Hollow portion.

Claims

1. A centrifugal compressor, characterized in that: have: a vortex housing forming a vortex flow path; a shroud member mounted in the scroll housing at a position radially inward of the scroll flow path and having a shroud portion radially opposed to the compressor impeller; and a throttle member disposed in a gap formed between the scroll housing and the shroud member; The throttle member is configured to be movable to a protruding position protruding into the intake air flow path and a retracted position retracted from the intake air flow path. The scroll housing has an abutment portion that abuts against the shroud member in the axial direction of the compressor impeller and is arranged radially outside the throttle member. The abutment portion abuts against an axial end surface of the shroud member in which the gap is formed in the axial direction.

2. The centrifugal compressor according to claim 1, characterized in that The throttle member is arranged at a position farther from the shroud portion than a front edge of the compressor impeller.

3. The centrifugal compressor according to claim 1, characterized in that A sealing member is provided that is arranged between the scroll casing and the shroud member.

4. The centrifugal compressor according to claim 2, characterized in that A sealing member is provided that is arranged between the scroll casing and the shroud member.

5. The centrifugal compressor according to any one of claims 1 to 4, characterized in that: The shroud member forms a portion of the inner peripheral surface of the scroll flow path.

6. The centrifugal compressor according to any one of claims 1 to 4, characterized in that The shroud component comprises a wear-resistant material.

7. The centrifugal compressor according to any one of claims 1 to 4, characterized in that The shield member has a hollow portion.

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